Citation Nr: 21073313 Decision Date: 12/08/21 Archive Date: 12/08/21 DOCKET NO. 16-24 766 DATE: December 8, 2021 REMANDED Entitlement to service connection for a low back disorder, to include as secondary to service-connected left knee and leg disabilities, is remanded. Entitlement to service connection for a sciatic nerve disorder, to include as secondary to a low back disorder and to service-connected left knee and leg disabilities, is remanded. REASONS FOR REMAND The Veteran served on active duty from March 1973 to March 1993. The case comes before the Board of Veterans' Appeals (Board) on appeal from a May 2013 rating decision issued by the Department of Veterans Affairs (VA) Regional Office (RO). The Veteran testified at a hearing before the undersigned Veterans Law Judge in August 2019. A transcript of the proceeding is of record. The Board remanded the case for further development in November 2019. The case has since been returned to the Board for appellate review. Upon review, the Board finds that additional development is needed prior to adjudication of the issues on appeal. An August 2014 VA examiner opined that the Veteran's back disorder is less likely than not proximately due to or the result of his service-connected left knee and leg disabilities. In rendering her opinion, she indicated that there is no documentation of a prolonged gait abnormality due to the service-connected disabilities. She explained that a chronic gait abnormality for 20 to 30 years would have been expected to cause the eventual development of degenerative changes at all levels of the lumbar spine, whereas the Veteran's pathology on imaging is mild and is limited to the L5-S1 level. However, the examiner did not address the aggravation prong of secondary service connection. Thereafter, a February 2020 VA examiner provided a medical opinion regarding direct service connection for a low back disorder. However, she did not address secondary service connection. As such, there is no medical opinion addressing whether the Veteran's service-connected left knee and leg disabilities may have aggravated his low back disorder. See 38 C.F.R. § 3.310; El-Amin v. Shinseki, 26 Vet. App. 136, 140-41 (2013). Therefore, the Board finds that an additional medical opinion is needed. The Board also finds that the low back disorder and sciatica nerve disorder are inextricably intertwined. See Harris v. Derwinski, 1 Vet. App. 180, 183 (1991). The matters are REMANDED for the following action: 1. The agency of original jurisdiction (AOJ) should request that the Veteran provide the names and addresses of any and all health care providers not already of record who have provided treatment for the issues on appeal. After acquiring this information and obtaining any necessary authorization, the AOJ should obtain and associate these records with the claims file. The AOJ should also obtain any outstanding VA medical records. 2. After completing the foregoing development, the AOJ should request a VA medical opinion to determine the nature and etiology of any low back disorder that may be present. A physical examination is only needed if deemed necessary by the examiner. The examiner is requested to review all pertinent records associated with the claims file, including the Veteran's service treatment records, post-service medical records, assertions, and August 2019 hearing transcript. It should be noted that the Veteran is competent to attest to matters of which he has first-hand knowledge, including observable symptoms. If there is a medical basis to support or doubt the history provided by the Veteran, the examiner should provide a fully reasoned explanation. The examiner should also opine as to whether it is at least as likely as not that the Veteran has a low back disorder that is either caused or aggravated by his service-connected left knee and leg disabilities. The Veteran has claimed that the service-connected disabilities have altered his gait and the way he lifts, which resulted in a low back disorder. See e.g. January 2014 statement. In rendering his or her opinion, the examiner should address both the causation and aggravation questions in his or her rationale. In other words, even if the Veteran's service-connected left knee and leg disabilities did not cause the Veteran's low back disorder, the examiner should still address whether his service-connected disabilities worsened his low back disorder. (The term "at least as likely as not" does not mean within the realm of medical possibility, but rather that the medical evidence both for and against a conclusion is so evenly divided that it is as medically sound to find in favor of a conclusion as it is to find against it.) A clear rationale for all opinions would be helpful and a discussion of the facts and medical principles involved would be of considerable assistance to the Board. 3. The AOJ should ensure compliance with the prior directives and conduct any other development as may be indicated. J.W. ZISSIMOS Veterans Law Judge Board of Veterans' Appeals Attorney for the Board R. DeVerter, Associate Counsel The Board's decision in this case is binding only with respect to the instant matter decided. This decision is not precedential and does not establish VA policies or interpretations of general applicability. 38 C.F.R. § 20.1303.